Method and apparatus for producing variable denier yarn



Jan. 12, 1960 R. F. DYER 2,920,345

METHOD AND APPARATUS FOR PRODUCING VARIABLE DENIER YARN Filed June 3,1955 3 Sheets-Sheet 1 L *1 I ll 34 E {a Richard .E'Dyer IN V EN TOR.

Jan. 12, 1960 R. F. DYER 2,920,345 METHOD AND APPARATUS FOR PRODUCINGVARIABLE DENIER YARN I Filed June 3. 1955 r 3 Sheets-Sheet 2 I I l I I 026 4'0 60 so 100 d u H U c -//vc//s0/= YARN T F1931) CENTER FjgZ INCHESOF WIRN I I I I I I 0 2o 4o 60 so 100 F 3 INCHES 0F YARN RichardE'DyerIN V EN TOR.

Jan. 12, 1960 R. F. DYER 2,920,345

METHOD AND APPARATUS FOR PRODUCING VARIABLE DENIER YARN Filed June 5',1955 1 3 Sheets-Sheet 3 DEN/ER l I 0 2O '40 60 80 I00 I g Y I I INCHESOF mRN Fig4b I Richer-d1? pger INVEMTORL Patented Jan. 12, 19692,920,345 IVIETHOD AND APPARATUS FOR PRODUCING VARIABLE DENIER YARNClaims. (Cl. 18-8) Tenn., assign'or to Eastman Rochester, N.Y., acorporation of The present invention relates to more particularly to amethod of ing a variable denier yarn.

There is a continuous demand by fabric designers for a thick and thinacetate yarn having very closely spaced slubs or short heavy denierlengths to impart a novel appearance to fabric woven from the yarn.Heretofore, while it has been possible to produce thick and thin acetateyarn with closely spaced thick slubs, the very low spinning speedrequired to achieve yarn quality has made such a yarneconomically'unfeasible. As a result, most commercially available thickand thin yarns have slubs spaced from 30-50 inches apart. Moreover, thehigh mechanism speeds required for producing slub acetate yarn, athigher spinning speeds, made the design of the mechanism complicated andsubject to excessive breakage.

The invention has as its principal object the provision of a method ofmaking closely spaced slubs in acetate yarn at economically feasiblespinning speeds without impairment of yarn quality.

A further object of the invention is the provision of a simple, reliablemechanism capable of operating at high speeds in a manner to produceclosely spaced slubs of acetate yarn.

Another object of the invention is the provision of a method of and theapparatus for producing slub yarn having novel patterns of variations indenier.

In essence, the invention consists of randomly and intermittentlyvibrating a spring restrained guide lever so as to increase and decreasealternately the relative drafting force on the yarn by pulling on andreleasing the yarn.

To these and other ends, the invention resides in certain improvementsand combinations of parts all as will be hereinafter more fullydescribed, the novel features being pointed out in the claims at the endof the specification.

In the drawings:

Fig. 1 is a schematic representation of an acetate yarn spinning device,showing the relation thereto of one modification of a slub formingmechanism constructed in accordance with the present invention;

Fig. 2 is a diagrammatic view of the pivoted or movable yarn guideshowing the sequence of operations thereto to provide the series ofoscillations which provide the desired type of slub yarn;

Fig. 3a is a typical denier variation chart of one type of thick andthin yarn produced by the apparatus and method of the present invention;

Figs. 3b and 30 show variations of the slub effect which can be made bysuitable adjustments of the mechanism of the present invention;

Fig. 4a shows a modified movable slub lever guide constructed inaccordance with another embodiment of the invention; and

Fig. 4b shows a denier variation chart produced from the leverconstruction illustrated in Fig. 412.

Similar reference numerals throughout the various views indicate thesame parts.

yarn production, and and apparatus for formon the cam 43 to free Fig. 1of the drawings shows yarn filaments 11 which are extruded from aspinnerette 12 into curing cabinet 13. The cured yarn is passed througha small opening 14 in the bottom of the cabinet 13. This yarn is thenpassed over a slubbing guide 15 which supplies a light tension to theyarn. The latter then passes through a top fixed guide 16, a loop 35 ofa slubbing lever guide, broadly designated by the numeral 17, through abottom fixed guide 18 and finally over a godet roll 19. From this point,any of several means may be used to wind the yarn up for subsequentprocessing. It will be noted that the bottom fixed guide 18 is invertical alignment with the top fixed guide 16 and cooperates therewithto provide a straight path 20, shown in dotted lines, if the slubbinglever guide 17 were removed or inoperative.

The slubbing lever guide 17 is pivoted at 25 for free rocking in ahorizontal plane and normal to path 20 as is deemed apparent from aninspection of Fig. 1. The horizontal movement of the lever 17 isrestrained by two opposing springs 26 and 27 having adjacentendsconnected to lever 17, and opposite ends 30 and 31 respectivelyanchored at 32 and 33 to a suitable, stationary support 34, all as shownin Fig. 1. It will be apparent from the above description and viewing ofFig. 1,

that if the lever 17 is displaced horizontal from the' center position,see Fig. 2, and suddenly released, the opposing springs 26 and 27 willcause the lever to vibrate at the natural frequency of the system toprovide a series or plurality of oscillations of progressivelydecreasing size or amplitude, as shown in Fig. 2. The frequency ofvibration can be controlled by the stiffness of the springs 26 and 27,Le. stiff springs cause a higher frequency. Also, the frequency ofvibration canbe controlled by the weight of the lever itself; aheavylever vibrates slower because of its greater inertia. The action of theyarn on the lever, of course, is to return the lever to its centralposition and oppose any removal-therefrom. Since the yarn exertsmorerestraint on the lever 17 during its motion away from the center thantowards the center, the yarn acts to dampen out or subdue the vibrationsof the lever. I

An endless moving chain, or similar member 40, is provided with aplurality of pins 41 spaced therealong, only two of these pins beingshown in Fig. l. The chain 40 is moved to the right by any suitablemechanism to bring successively the pins 41 into engagement with anoffset or cam portion 43 formed on lever 17.

Such engagement serves to move or rock lever 17 to the right about itspivot 25 to move the lever and yarn laterally or in a direction normalto the path 20 between guides 16'and 18. The contact of each pin 41 andcam 43 is continued until the lever 17 has been moved far enough to theright, Fig. 1, allowing the pin 41 to ride the lever 17. The result isthat the springs 26 and 27 cause the lever 17 to continue to oscillateback and forth through its center position on the vertical axis of theguides 16 and 18. As isapparent from Fig. 2, these oscillations are ofprogressively smaller and smaller amplitude.

The eitect of these oscillations of the slubbing lever guide 17 is toincrease the spinning speed or draft and cause lower denier as the levermoves to the right of center, suddenly to decrease the draft and make aheavier denier slub as the lever moves back toward center, to suddenlyincrease the draft and reduce the denier as the lever moves to the leftof center, and then suddenly decrease the draft to make a slub asthelever. returns toward the center. These oscillations of the leverv 17and the production of alternately thick and thin spots in the yarncontinues to decrease progressively, until the yarn tension dampens outand stops the vibration, or until the next chain pin 41 stops thevibration sequence and'sets up a new series of vibrations. Of course,the dampening efiect of the yarn tension on the lever vibration causeseach successive cycle of vibration to be smaller, and a gradual orprogressive decrease in the variation in the denier between the slubsand the thin spots takes place.

Referring to Fig. 2, a plan view of lever 17 is shown with extreme rightand left positions of the lever with successive oscillations being shownin alphabetical sequence. Fig. 3a shows the corresponding variations indenier, and is lettered to correspond to the lever positions of Fig. 2.It should be kept in mind at this point that the low denier sections ofyarn are made during the pull-out movement of the yarn away from thecenter position, and the heavier denier sections are made during themovement of the lever toward its center position.

It might be thought that the fixed frequency of oscillation of the leverwould produce evenly spaced slubs, which would cause undesirablepatterns in fabric woven from the yarn. In practice, only four or fivesuccessive evenly spaced slubs are made before the denier variationsdecrease to a negligible amount. Moreover, the pins 41 on the chain 40,which initiates the vibrations, are randomly spaced. Thus, although thefour or five slubs in any group are evenly spaced, the group of slubs israndom in occurrence in the yarn, and this has been found to besutficient to avoid any pattern of slubs.

Certain interesting variations in the slub pattern can be made byvarying the adjustments of the springs 26 and 27. For example, if spring27 of Pig. 1 is made tighter than spring 26, the slubber lever guide 17will not come to rest at the center; but, on the contrary, will actuallycome to rest on the right of center. This will cause a decrease in itsexcursions to the left of center and then cause smaller pull-outs to theleft and hence smaller slubs. With this setup, the slub pattern is:large slub, small slub, large slub, small slub, etc. as shown in Fig.3b. By use of a heavy slubbing lever, the vibrations can be prolongedand if chain 40 is moved slowly a long series of slubs, say five to ten,can be made in each group of slubs and the denier pattern as shown inFig. 3c can be made.

Fig. 4a shows a modified form of slubber lever guide 46. In thisembodiment the support 45 for the slubber lever guide 46 is formed witha flat portion 47 against which a bowed leaf spring 43 bears to exert aheavy restraining force on lever 46 only in the center position. Theends of the spring 48 are anchored at 49. This arrangement causes thelever 46 to stop oscillating after only two or three pull outs, and willproduce the slub pattern shown in Fig. 4b if the chain speed is notchanged. Other novel effects may be produced by combinations andvariations in the lever weight, shape, spring tensions and frictionaldrag placed on the slubber lever. In this embodiment, lever 46 hasconnected thereto springs 50 and 51 which are similar or identical tosprings 26 and 27, Fig. 1.

It may be wondered why it was not possible to speed up the chains orcams of the slubber mechanisms to obtain closer slub spacings. However,when this was done, the yarn strands were broken at the spinnerette. Itis believed that such breakage occurs because of frequent, forcefulinterference with natural longitudinal force waves set up in the yarnstrands by the formation of each slub. The pull out action caused by thecams of prior mechanisms Was positive and the only yieldable portion ofthe system was the yarn which had to give. In the mechanism of thepresent invention, on the other hand, springs 26 and 27 or 50 and 51 arelight, and exert very light force. Lever 17, or 46, is also light andfreely pivoted. Thus, the forces in the yarn are relatively strongenough to obtain some yielding in the slubber mechanism. The result isthat the instantaneous transient stresses in the yarn are not as greateven though they are more frequent, and the chance of breaking the yarnstrand is appreciably reduced. It has been found possible to reduce thespots between slubs to about 8" or 9 compared with 30" to 5 in the caseof prior mechanisms.

It will be apparent that the substitution of a helical coil springlocated at the lever guide pivot point, or other variations of springarrangements in substitution for springs 26 and 27 or 50 and 51, willnot violate the spirit of the invention. Also, it would be possible tomake the slubber lever itself out of spring material and mount it in afixed position at its pivot point and eliminate the strain on springs 26and 27 or 50 and 51.

The present invention thus provides a novel mechanism and a method forforming a variable denier yarn. ideally, the springs 26 and 27 or St)and 51 are always in a state of tension and are never compressed. Thus,the motion of the slubbing lever is controlled entirely by the tensionof the springs and the force of the yarn tension on the lever, andapproximately harmonic motion is the result. Due to the geometry of theline of motion of the chain pins and the pivot point of the slubbinglever, the latter travels with a harmonic motion when under theinfluence of the chain pins as well as after it is released when itcomes under the influence of the springs, yarn tension and frictionalforces. The harmonic motion of the lever under control of the chain pinsis obvious, however, only a portion of a complete harmonic cycle ofmotion, while the springs cause several complete cycles of anotherharmonic motion.

While certain embodiments of the invention have been disclosed, it isunderstood that the inventive idea may be carried out in a number ofways. This application is, therefore, not to be limited to the precisedetails described, but is intended to cover all variations andmodifications which fall within the scope of the appended claims.

What I claim and desire to secure by Letters Patent of the United Statesis:

1. In an apparatus for producing a variable denier yarn, the combinationwith yarn forming means, of fixed guide means for guiding said yarn fromsaid forming means along one path, means for imparting a harmonic motionto said yarn to form abrupt variations in the denier of said yarn, saidimparting means comprising a pivoted lever engaging said yarn betweensaid fixed guide means, means periodically engaging said lever to movethe latter and said yarn in a direction normal to said path, and springmeans associated with said lever for imparting a multioscillationharmonic motion of decreasing amplitudes to said lever in said directionto provide a plurality of abrupt variations in the denier of said yarn.

2. In an apparatus for producing a variable denier yarn, the combinationwith yarn forming means, of fixed guide means for guiding said yarn fromsaid forming means along one path, means for imparting a harmonic motionto said yarn to form abrupt variations in the denier of said yarn, saidimparting means comprising a pivoted lever engaging said yarn betweensaid fixed guide means, means periodically connected to and engagingsaid lever to move the latter and said yarn in a direction normal tosaid path, and flexible means connected to said lever for imparting aharmonic motion to said lever in said direction to provide a pluralityof progressively decreasing cycles of yarn oscillations in saiddirection to provide a plurality of abrupt yarn variations ofprogressively decreasing size.

3. In an apparatus for producing a variable denier yarn, the combinationwith yarn forming means, of fixed guide means for guiding said yarn fromsaid forming means along one path, means for imparting a harmonic motionto said yarn to form abrupt variations in the denier of said yarn, saidimparting means comprising a movable lever engaging said yarn, anendless moving member, means on said member periodically engaging saidlever to move the latter in a direction normal to said path, and springmeans connected to said lever to move the latter in said direction in aseries of oscillations to impart a plurality of abrupt variations in thedenier of said yarn between each actuation of said lever by said leverengaging means.

4. In an apparatus for reducing a variable denier yarn, the combinationwith yarn forming means, of fixed guide means for guiding said yarn fromsaid forming means along one path, means for imparting a harmonic motionto said yarn to form abrupt variations in the denier of said yarn, saidimparting means comprising a movable lever engaging said yarn, anendless moving member, means on said member periodically engaging saidlever to move the latter in a direction normal to said path, and springmeans connected to said lever to impart a harmonic motion to said leverto provide a series of decreasing cycles of yarn oscillations to form aplurality of abrupt yarn denier variations of decreasing size betweeneach actuation of said lever by said engaging means.

5. In an apparatus for producing a variable denier yarn, the combinationwith yarn forming means, of fixed guide means for guiding said yarn fromsaid forming means along one path, means for imparting a harmonic motionto said yarn to form abrupt variations in the denier of said yarn, saidimparting means comprising a yarn engaging lever, means to pivot saidlever adjacent one end thereof, a yarn guide positioned on the other endof said lever, an endless moving member, pins spaced along said memberand periodically engaging said lever to rock said lever about said pivotto shift said yarn in a direction normal to said path, and spring meansconnected to said lever to impart a harmonic movement to said lever in adirection normal to said one path to irnpart cycles of decreasing yarnoscillations to provide a plurality of abrupt yarn denier variations ofprogressively decreasing sizes.

6. In an apparatus for producing a variable denier yarn, the combinationwith a pair of spaced fixed yarn guides to direct the yarn along onepath, of means positioned between said guides for producing abruptvariations in the denier of said yarn, said means comprising a movableyarn guide, an endless moving member, a pin on said movable memberengaging said movable guide to move the latter and said yarn in adirection normal to said path, said pin finally moving out of engagementwith said movable guide to free the latter, and spring means connectedto said movable guide to impart to the latter a series of oscillationsof progressively decreasing amplitude in said direction to form aplurality to form a plurality of abrupt yarn denier variations ofgradually decreasing sizes along the yarn.

7. In an apparatus for producing a variable denier yarn, the combinationwith a pair of spaced fixed yarn guides to direct the yarn along onepath, of means positioned between said guides for producing abruptvariations in the denier of said yarn, said means comprising a pivotedyarn guide, an endless moving member, a plurality of pins spaced alongsaid member, the pins being movable progressively into engagement withsaid pivoted guide to move the latter and the yarn in a direction normalto said path, at the end of each of said last movements the pivotedguide moving out of contact with the pin to free the pivoted guide, anda pair of springs connected in opposed relation to said pivoted guide toimpart to the freed pivoted guide a series of oscillations ofprogressively decreasing magnitude in a direction normal to said path toprovide a series of abrupt yarn denier variations of progressivelydecreasing sizes along the length of said yarn.

8. In an apparatus for producing a variable denier yarn, the combinationwith a pair of spaced fixed yarn guides to direct the yarn along onepath, of means positioned between said guides for producing abruptvariations in the denier of said yarn, said means comprising a pivotedlever, a yarn guide on the free end of said lever engaging said yarnbetween the fixed guides, an endless moving member, a plurality of pinsspaced along said member, each of said pins being movable intoengagement with said lever to pivot the latter to move the guide thereonand the yarn in a direction normal to said path, the pin finally movingout of engagement with said lever to free the latter, and a pair ofsprings connected to opposite sides of said lever to impart to the freedlever a series of oscillations of progressively decreasing magnitude ina direction normal to said path to provide a series of abrupt yarndenier variations of progressively decreasing size along the length ofthe yarn between successive engagements of the pins with said lever.

9. An improved yarn oscillating apparatus for varying the denier offreshly spun yarn of uniform denier by oscillating the yarn transverselyof a normal path along which the yarn runs between a pair of spaced,fixed guides and while the yarn is so running, said apparatus comprisinga guide means supported for oscillation across said normal path betweentwo extreme positions of oscillation, resilient means normally biasingsaid guide to a position between said extreme positions in the vicinityof said path, said resilient means being adapted upon impulse to impartto said guide means an harmonic motion comprising a series ofoscillations of decreasing amplitudes across said path, and means forsupplying impulses to said resilient means at predetermined intervals oftime.

10. An improved yarn oscillating apparatus for varying the denier ofyarn by oscillating the yarn while the yarn is running along a normalpath between a pair of spaced, fixed guides, said apparatus comprising aguide means adapted to oscillate across said path between extremepositions on opposite sides thereof, said guide means providing a yarnguiding surface which contacts yarn on said path between said fixedguides, intermittent means adapted to repeatedly engage and successivelydisengage said guide means, said intermittent means being adapted uponengagement thereof with the guide means to move the guide means awayfrom said normal path toward one of the extreme positions, and resilientmeans normally biasing said guide means to said position between saidextreme positions and in the vicinity of said path, said resilient meansbeing adapted to impart to said guide means upon disengagement therefromof the intermittent means and prior to subsequent engagement thereof adamped harmonic motion comprising a series of oscillations of decreasingamplitudes, said oscillations crossing said path.

References Cited in the file of this patent UNITED STATES PATENTS771,720 Damon et al. Oct. 4, 1904 2,038,722 Dreyfus et al. Apr. 28, 19362,064,279 Taylor et al. Dec. 15, 1936 2,152,222 Taylor et al Mar. 28,1939 2,293,981 Jackson Aug. 25, 1952 FOREIGN PATENTS 175,829 GermanyAug. 25, 1953 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIONJanuary 12, 1960 Patent No. 2,920,345

Richard F. Dyer It is hereby certified that error appears in the-printed specification of the above numbered patent requiring correctionand that the said Letters Patent should read as corrected below.

Column 5, line 4, for "reducing" read producing line 48, strike out "toform a plurality".

Signed and sealed this 12th day of July 1960.

(SEAL) Attest: KARL H. AXLINE ROBERT C. WATSON Attesting OfficerCommissioner of Patents

